Electric discharge device



June 11, 1940. o. BAKER 2,204,204

, ELECTRIC DISCHARGE DEVICE Filed May 15, 1953 Fly. 7 F49, 3

Mffarney patented June 11, 1946 PATENT OFFICE ELECTRIC DISCHARGE DEVICE Otto Baler, Berlin,

Germany,

assignor to C.

Lorenz Aktiengcsellschaft, Berlin-Tempelht, Lorenzweg, Germany, a company Application May 13, 1938, Serial No. 207,753 In Germany May 13, 1937 1 Claim.

The present invention relates to electric discharge devices and more particularly to electronic discharge tubes adapted for operation at very high frequencies.

Discharge tubes of the so-called acorn type have recently been employed for generating and receiving very high frequencies. The discharge vessel of such tubes is composed of two portions which are intimately united with one another, whereby the leading in conductors to the.various electrodes of the discharge device are fixed in the joint so as to project radially from the vessel.

Other types of high frequency discharge tubes are known in which the tube envelope consists of ceramic material, the leading-in conductors being sealed in the envelope by means of a vitreous seal. The sealing in correct spaced relationship of the leading-in conductors of the electrode system to the portions of the envelope which consist of ceramic material is rather difficult.

The present invention has for its object to avoid the difliculties involved during the manufacturing process. This is accomplished in connection with tubes having a ceramic base portion by providing the lcading-in conductors and the supporting wires with a portion which is adapted to extend radially with respect to the longitudinal axis of the tube and which may be fixed in position during the sealing operation by means of suitable tools or similar devices.

The invention will be more readily understood from the following description taken in conjunction with the accompanying drawing in which Fig. l is a longitudinal cross section through one embodiment according to the invention, Fig. 2 is a bottom view of another embodiment of similar construction as Fig. 1, Fig. 3 shows a further modification of the base portion according to the invention, while Fig. 4 is a view as seen from below of a device of a type shown in Fig. 3.

Referring to the figures, reference numeral I indicates a cylindrical body to which the topportion 2 of glass is sealed at 8. These two members form the envelope of the tube. The cylinder l is intimately united with a disc-shaped member 3 of ceramic material by a vitreous seal 9, for example. The holes 5 are adapted to receive the leading-in conductors 4 of the electrode system 6. These conductors are sealed to the base portion 3 in the holes 5 as shown by the seal 5 by the agency of a glass bead or the like. The leads 4 comprise two integral portions arranged at right angles to one another, whereby the leg not sealed to the base portion or plate 3 extends radially outwards. The shape of the leading-in conductors and supporting wires as above described involves the advantage that these members may be fixed in a tool or gauge relative to one another during the sealing process so as to maintain their relative positions after finished sealing which considerably facilitates the attachment to a tube socket or corresponding fitting.

A further modification according to the invention is illustrated in Fig. 3 in which the envelope has been deleted for the sake of simplicity. Also this structure discloses radially extending leads 4. The base plate 3 is provided with an annular projection 1 having radial slots in which the leads 4 are placed so as to prevent displacement of these leads during the sealing operation. Moreover, the present arrangement involves the advantage that the leads cannot be subjected to movements or bendings which under circumstances might cause damages of the sealing points or of the seal itself by glass bead splintering.

The leading-in conductors are preferably sealed to the base plate by the agency of a material having a higher melting point, such as hard glass, for instance. This sealing process is conveniently achieved in such manner that the base plate together with the leads, wires and the glass beads is arranged in a tool or fixing device whereupon the entire assembly is placed in a furnace at very high temperature. The advantages of the above described arrangement of fixing the leads with respect to the base portion of the tube are particularly accentuated in the course of this step of operation during which mutual displacement between the leads to be sealed easily may occur.

The succeeding steps of the tube manufacturing are accomplished in such manner that after the leads have been sealed to the base plate, the electrode system 6 is attached to the pertaining leads by the aid of suitable gauges or other similar devices so as to provide accurate inter-electrode spaces, whereupon the cylinder 1 is placed in position and intimately united with the base portion by means of a vitreous melt having a. melting point which is lower than that of the material used for sealing the electrodes to the base plate. This operation may be eifected by heating the entire tube in a furnace.

The above described electronic discharge tube and the method of manufacturing such tubes present the specific advantage that the leading-in conductors may be accurately fixed although very high temperatures are used during the sealing operation. A further advantage is involved on account of the fact that the tube can be manufactured in individual steps, that is, the base plate and the electrode leads are at first assembled, whereupon the electrodes are attached to the leads. Finally, the envelope is fixed to the base portion of the tube.

What is claimed is:

An electric discharge tube comprising an en velope, a base portion of ceramic material having radial slots and being united with said envelope,

a plurality of electrodes located within said envelope, and leading-in conductors to said electrodes, said leading-in conductors passing perpendicularly through said base portion and having portions extending at right angles through said slots radially outwards with respect to the centre of the tube.

OTTO BAIER. 

